namespace Lucene.Net.Search
{
    using BytesRef = Lucene.Net.Util.BytesRef;

    /*
         * Licensed to the Apache Software Foundation (ASF) under one or more
         * contributor license agreements.  See the NOTICE file distributed with
         * this work for additional information regarding copyright ownership.
         * The ASF licenses this file to You under the Apache License, Version 2.0
         * (the "License"); you may not use this file except in compliance with
         * the License.  You may obtain a copy of the License at
         *
         *     http://www.apache.org/licenses/LICENSE-2.0
         *
         * Unless required by applicable law or agreed to in writing, software
         * distributed under the License is distributed on an "AS IS" BASIS,
         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
         * See the License for the specific language governing permissions and
         * limitations under the License.
         */

    using FilteredTermsEnum = Lucene.Net.Index.FilteredTermsEnum;
    using StringHelper = Lucene.Net.Util.StringHelper;
    using TermsEnum = Lucene.Net.Index.TermsEnum;

    /// <summary>
    /// Subclass of FilteredTermEnum for enumerating all terms that match the
    /// specified prefix filter term.
    /// <p>Term enumerations are always ordered by
    /// <seealso cref="#getComparator"/>.  Each term in the enumeration is
    /// greater than all that precede it.</p>
    /// </summary>
    public class PrefixTermsEnum : FilteredTermsEnum
    {
        private readonly BytesRef PrefixRef;

        public PrefixTermsEnum(TermsEnum tenum, BytesRef prefixText)
            : base(tenum)
        {
            InitialSeekTerm = this.PrefixRef = prefixText;
        }

        protected internal override AcceptStatus Accept(BytesRef term)
        {
            if (StringHelper.StartsWith(term, PrefixRef))
            {
                return AcceptStatus.YES;
            }
            else
            {
                return AcceptStatus.END;
            }
        }
    }
}